The present invention relates to what are commonly called crossflow or directional valves used for redirecting large quantities of water in cooling towers.
Normally the water used in cooling towers is fed by means of supply pipes near or at the top of such towers, these pipes usually being supported in a horizontal position. In order to change the direction of the water flow so that it may drop through the cooling tower, a valve is connected to the open end of a given pipe (one of several terminating near the top, of the tower) that by virtue of its shape diverts the water flow to a vertically downward direction. Such valves normally employ a reciprocating valve face or plate, usually in the form of a disc whose perimeter corresponds to that of the water pipe as well as that of an upper part of the valve housing in which it is disposed, so that in one position the disc sealingly abuts against the end face of the water pipe and in another position it is removed therefrom, thus allowing the water to change direction within the valve housing as above described. To reciprocate the disc plate away from the end face of the water pipe a valve stem supporting the disc plate at its center is normally threaded into a bushing in an opposing wall of the valve housing. Turning the stem from the outside of the housing one way or the other moves the disc plate towards or away from the pipe port or opening. This relatively simply valve structure serves the binary purpose of either opening or closing off water flow, but between these two extremes the disc plate, valve stem and bushing are subjected to undue strain and wear, owing to the chatter and movement that these parts experience as they are submitted to the turbulence of the water stream. There is a need, therefore, to provide a directional valve of the kind above described, which will not subject its moving parts to undue wear and strain when opening and closing the valve and when attempting to regulate water flow (during attempts to balance flow on hot water decks, for example).